Structural Mechanics Third Edition Long Yuqiu Higher Education Press
The fifth edition of Mechanics of Materials Sun Higher Education Press.
The textbook of higher education edition is authoritative in this respect. I have learned two of these three books, theoretical mechanics is very classic, and it is already the sixth edition. The teaching and research section of Harbin Institute of Technology has graduated from two academicians of the Academy of Engineering, and its strength can be imagined. Many people are learning the Long Yuqiu version of structural mechanics, and many reference materials for college entrance examination are also in this version. If I have material strength, I learned it from my own school, but this one can be said to have a high evaluation, and it is already the fifth edition.
I hope it helps you.